President Obama vowed once again to “try to make progress” on issues like immigration reform, reducing student debt and ensuring equal pay for women by using his executive authority as long as Congress remains gridlocked, he said at a press conference Wednesday.

“The American people don’t want me just standing around twiddling my thumbs and waiting for Congress to get something done,” the president said in response to a question from ABC News' Jonathan Karl.

I’m bound by the Constitution,” Obama acknowledged. “I’m bound by separation of powers. There are some things we can’t do.”

“But the president said his preference was “to work with Congress, because not only can Congress do more but it’s going to be longer lasting.”

For example, Obama said he would “love to fund” large infrastructure projects that would put Americans to work “but without the cooperation of Congress,” there are other options at his disposal.

“What I am consistently going to do is wherever I have the legal authorities to make progress,” he said. “I’m going to seize those opportunities.”

When it comes to immigration reform, Obama dismissed Republican claims of executive overreach noting that he never has a “green light” to act unilaterally.

“We have a broken system, it’s under resourced, and we’ve got to make choices in terms of how we allocate personnel,” he said at the close of a three-day summit on U.S.-Africa relations, “and that’s well within our authorities.”

On the issue of Israel, Obama several times said he has “no sympathy for Hamas.”

“No country would tolerate rockets being launched into their cities,” the president said. “I have consistently supported Israel’s right to defend itself … I also think it is important to remember that Hamas acts extraordinarily irresponsibly when it is deliberately sighting rocket launchers in population centers.”

The president said the international community – especially diplomats negotiating in Egypt - must now focus on ensuring that the ceasefire holds and allow Israel to finish closing off the network of underground terror tunnels Hamas dug below the city.

“Long term, there has to be a recognition that Gaza cannot sustain itself permanently closed off,” Obama said. “The question then becomes, can we find a formula in which Israel has greater assurance that Gaza will not be a launching pad for further attacks … but at the same time, ordinary Palestinians have some prospects for an opening of Gaza so that they do not feel walled off.”

A permanent reconciliation will involve significant risk, the president acknowledged, but the Palestinian authority in the West Bank have “shown themselves to be responsible, they have recognized Israel, [and] they are prepared to move forward to arrive at a two-state solution.”

Obama called for a “slow rebuilding of trust” so that “the people of Gaza feel some sense of hope and the people of Israel feel confident that they’re not going to have a repeat of the kind of rocket launches that we’ve seen over the last several weeks.”